\name{GetID}
\alias{GetID}
%- Also NEED an '\alias' for EACH other topic documented here.
\encoding{UTF-8}
\title{
Gets ID of the Geometry
}
\description{
获取几何对象的ID
}
\usage{
GetID(obj)
}
%- maybe also 'usage' for other objects documented here.
\arguments{
  \item{obj}{
几何对象
}
}
\details{
%%  ~~ If necessary, more details than the description above ~~
}
\value{
成功返回几何对象的ID，否则，返回-1
}
\references{
%% ~put references to the literature/web site here ~
}
\author{
%%  ~~who you are~~
}
\note{
%%  ~~further notes~~
}

%% ~Make other sections like Warning with \section{Warning }{....} ~

\seealso{
\code{\link{SetID}}
}
\examples{
geo <- CreatePoint(10,20)
GetID(geo)
SetID(geo, 10L)
GetID(geo)
}
% Add one or more standard keywords, see file 'KEYWORDS' in the
% R documentation directory.
\keyword{ supermap }% use one of  RShowDoc("KEYWORDS")
\keyword{ID}